For analyzing materials present as individual pieces, for example, biological material, such as seeds of cereals and so on, and others, by, for example, spectroscopic analysis and the like, by irradiation with an electromagnetic ray, such as an infrared ray or so on, each individual piece of material is first secured on a sample holder and the analysis is performed on the so-secured sample of the material piece. In the case of analyzing, for example, seeds of a plant, seed samples are secured in receptacles formed on a sample holder in a definite arrangement and a definite posture, whereupon the analysis is performed on, for example, an analyzing surface formed, if necessary, on each seed sample by processing it by, for example, cutting and/or grinding. The analysis is performed in general in such a way that a plurality of receptacles for receiving each sample, such as sample compartments, are formed on a sample holder and each sample is secured in each of the receptacles, whereupon the so secured samples are subjected to the same analysis operation simultaneously or successively to obtain the analysis results for these samples in one single analysis course.
Heretofore, analysis samples were secured on the sample holder in general using an adhesive or a filler. However, this prior art method suffers from a problem that a uniform solidification time and uniform adhesion strength of the adhesive or filler are difficult to attain for all the samples.
Use of an adhesive in the form of a solution in a solvent will require considerable time for the removal of the solvent with concomitant reduction of the accuracy of the analysis due to contamination of the sample by the solvent.
In contrast thereto, use of an adhesive of a hardening type requires admixing of a hardening agent to the adhesive to initiate hardening, which accompanies a problem that introduction of the adhesive into a plurality of receptacles is not easy, often causing differences in the hardening conditions due to a possible discrepancy upon the introduction of the adhesive, resulting in an unequal hardening aspect for different samples. When the hardening is effected within a shorter period of time, the processibility of the sample deteriorates and, when the hardening takes a longer period of time, an extended time is required for attaining the requisite adhesion strength, resulting in a lower efficiency of the analysis.
When a cold-hardening adhesive, such as those based on an epoxy resin, is used, a proper analyzing surface, on which the analysis is performed, is difficultly formed by cutting and/or grinding the sample due to difficulty in maintaining the definite secured state of the sample steadily, since a cold hardening adhesive requires a considerable period of time for hardening at normal temperatures and complete hardening will hardly be attained at normal temperatures. When heating is incorporated for attaining complete hardening, the sample may be apt to suffer from denaturation from the heat.
On the other hand, when an instantaneously hardening adhesive is used, it exhibits a high permeability into organic matter and may cause denaturation of the sample, in addition to the problem of easy dripping down from the interspace between the sample and the receptacle inner wall due to its low viscosity.